Fluid pressure apparatus



Jan..2l, 1941. B. DICK FLUID PRESSURE APPARATUS Filed Aug. 25, 1939 w y .vdi m .Noi N.

. infill/i274?! l V/srs Patented Jan. 2l, 1 941 'Y UNITED STATES zazaqs':

FLUID PRESSURE APPARATUS Burns Dlk. Fermlon, Electric Corporation, tion of Delaware Mc.. einer to Warner Bt. Imis, llo., a corpora- Application Aunis# 25, 1939, Serial No. 291,853

lily invention relates to uid pressure apparates end more particularly to sealing means for preventing uid under pressure from passing bel tween ai cylinder wall and a piston reciprocable therein..

@ne or the objects of my invention is to provide e, sealing means for a 'piston and cylinder willen Will eflciently prevent leakage of iluid and else not be damaged during reciprocation of l@ the piston.

' il more specific object of my invention is toy nrevlele improved sealing means for a. reciproeeble piston which is provided with a head por- W tion tbnt projeets into an enlarged Huid con- Mi teleline: ebbe @tirer obieets of my invention will become apnotent trom the following description taken in eow-etion with the eccompanyinor drawing in vvliieli lillenre l is e eines-sectional view el" e.

'rieirble eisten dele meter construction provided itinere t in e eroeoweeetienel view taten on the line erlitten@ l.: end litem-ee t. and t ere m vir-ivre ei tbe in el tite annular plete emnleyeri M to nrevent demone te tire rubber een.

Itteierrlnn te the dren in detail, neral l inrllentee n eylinder meinber'vvhlelr lien secured te eeelr et ite endo by eeoneret threode, e nis ten, members `Within eeeli de member le n leisten t lien e ee-cylindricel treed il nreieetlnnj inte the. eylinrlerniber i vvliielr in ei terrier ollerneter tiren tbe ntilde membere.

tiene nlston is ionnecl vrlth'a shoulder t lor en- Em, tenement with the enel nl the nuide member to W limit tbe errtent ol innere movement of the ienton., 'lire heed el'y eeen bieten has associeted therewith e ilereble ene-shaped diaphree t merle oi rubber or like meterla! and snugly littine told lbeen and provided with a base 'l leed vritli. en nnneler lin e positioned against en en nirler oboirlder t on the piston guide portion. 'llre leone nnel the lin el' each cup are. held in Armsitien eeeinst the ahoulder byv an erin-oler M lieirline' meber it clamped between the cylinder end tbe eisten milde member. Peri'orations il in vtbe lrolrlinn members permit nuid to contoet the bese and the lip t of each cup. y

in lrin-oler to prevent the inner corner of the Vbeen nertion oi the nexlble cup from being lorced intel clearance-space between the wall of eeen bitten and Aits piston guide portion, there ie nrovlded a Split ring I2 which resiliently ene the wall of the piston and is positioned in -a recess it in ,the piston guide portion. The

55 width of the ring' and the recess are such that til litt

embodying my invention;

the end surface of the ring will be flush with the shoulder l. Interposed between the base orthe cup and the split ringl is a very thin annular metal plate Il which has a slightly larger inner diameter than the outer diameter of vthe piston 5 so as to be easily slipped thereover. The plate is of such radial width that it overlies the gap between the adjacent ends of the split ring and also any gap Il between the outer surface of the ring:anditsremessI3.y

The cylinder member l is privded with an inlet e It which ls connected by a conduit il with a suitable source of pressure, whereby the pistons can be moved apart when the :duid in the cylinder is placed under pressure. A bleeder outlet and screw le permits air to be bled from the cylinder. e eertieuler double piston motor ehown in eeneeielly ented for the actuation or breite sheet, tbe eyllnrler beine mounted upon t it end tbe plotone -lievine cooperating pieton rode it tu :l:` tbe ends oi tbe brake rbeee ti..r j

ln enerntion vvlien the duid in cylinder i ls roleoerl der nreeenre, tbe restons will be moved innert. 'Ellie iieirlble eline will be Ytoroed by tbe m tutti ln titlit ennnnement tvitlr the bends oi their nistons. nino, nele. under pressme neto on the bene "l el lin oi' eeeb een te meintain them in endettement tritli tbe einteilen they eontect. Due to tbe nini-,on rlnn end plete nrreneement, there is ne een erneeed inte tvbieli yl Dertien ol the meterl oi the bete el the eine een be forced.

'llene tbe een it nrevented irom beine ont or elievved vvlien tbe pieton ie reeinreented by the iiuiel under nreeetire. li tbe rine" enel plate were not nreeent, tbe eleernnce between tbe wall oi' tire bieten end tbe bieten de member would nerrnit e nortien el tbe teriel et the cnn to be ioreed therein under bien duid pressures and this nertlon vvenlel eesllyibe demencial er out and the emeleney ei the een imbeired. lleva/ever, i@ the nsetlon shown, tbie normel clearance bleelred edm by the split rine it and no clenrn enee is preeent because tbe resilient rind snugly enneeen tbe well oi tbe piston et ell times. Also, with tbe tbln plete il the een between the ends of the ne' end the een it between the ring and recess will not A'be exposed to` any portion of the base el the cup. Due to the thlnness ol plate it, the edge thereof cannot eut the cup even if the material oi the cup is forced into any slight clearance between its edge and the adjacent surface.

Althoughr the particular sealing means for the piston is shown as being applied toa iluid motor.

l it can also be incorporated in a iiuid pressure developing system wherein the piston is moved into the cylinder I to develop pressure instead or being moved by iiuid pressure.

Being aware of the possibility of modications in the particular structure herein described withexposed to the iluid in the chamber and havingl a clearance with said guide member. a flexible packing element carried by the` guide member and surrounding and engaging the wall of the piston, and means comprising a member can'ied by the guide member against movement with the Piston and associated with the packing element and resiliently engaging the wall of the piston at all times notwithstanding wear thereof for preventing iluid under pressure from forcing material of the packing element into said clearance 4 Space.

2. In apparatus of the class described, a fluid chamber, a piston guide member, a piston reciprocable in the guide member wtih its head exposed to the duid in the chamber and having a clearance with the guide member, a ilexible packing element carried by the guide member and surrounding and engaging the wall of the piston. and means comprising a split resilient ring capable of constantly engaging the piston wall surface notwithstanding wear thereof and interposed between -the packing element and the guide member forpreventing material of the packing element from being forced by fluid pressure into saidV clearance space.

3. In apparatus of the class described, a uid chamber, a piston guide member, a piston recip-4 rocable in the guide member with its head exposed to the fluid in the chamber and having a clearance with said guide member, a flexible packing element carried by the guide member and surrounding and engaging the wall of the piston, `means carried by the guide member against movement with the piston and associated with the packing element and the wall of the piston for preventing iluid under pressure from forcing any material of the packing element into said clearance space, said means comprising a split resilient ring engaging the wail of the plston, and a thin annular plate interposed between the ring and the packing element and covering the gap between the ends o! the ring.

4. In apparatus o! the class described, a iiuid chamber, a piston guide member, a piston reciprocable in the guide member and having its head projecting into the chamber, a flexible packing element surrounding the piston and positioned at the end of the guide member, a contractable split ring engaging the piston wall and received in a recess in the end of the guide member, and a thin annular plate interposed between the packe ing element and the ring and covering vthe gap between the ends of the ring.

5. In apparatus of the class described, a cylinder provided with a piston guide portion and an enlarged fluid receiving chamber, said cylinder having an annular shoulder and an annular recess at the end of the piston guide portion, a piston reciprocable in said guide portion and having its head extending into the chamber, a split ring in constant engagement with the outer wall surface of the piston and positioned in the recess to be flush with the surface of the'shoulder, an annular thin plate positioned in engagement with the shoulder and ring and covering the gap between the ends of the ring and any opening between the ring and the wall of the recess, and a flexible packing element surrounding the piston and positioned in engagement with the plate.

8. In apparatus of the class described, a cylinder provided with a piston guide portion and an enlarged uid receiving chamber, said cylinder `having an annular shoulder at the Juncture of the guide and chamber, a .piston reciprocable in the guide portion and provided with a semi-cylindrlcal head projecting into the chamber, a

semi-cylindrical flexible and extensible packing cup surrounding the head of the piston and having an annular flange at its base positioned adjacent the shoulder, means comprising an annular member carried by the guide portion and associated with the flange oi' the packing element and resilientLv engaging the wall of the piston at al1 times notwithstanding wear there-` of for preventing fluid under pressure from forcing material o! the packing element; into the clearance space between the wall surface of the piston and the cooperating surface of the guide portion, and a separable annular holdersecured 1 of the piston and having an annular ange at its base positioned adjacent the shoulder, a split ring positioned in the recess and resiliently engaging the outer wall surface oi.' the piston, an annular thin plate positioned between the flange of the cup and the shoulder and ring and covering the gap between the ends of the ring and any opening between the ring and the wall of the recess whereby said ange at the base of the cup is prevented from being forced into said gap and opening, and an annular holder secured to the cylinder and cooperating with the iiange of the cup for maintaining the latter in engagement a with the plate.

BURNS DICK.- 

